Help with my rom

Hi, Im mario from spain.
Well, i have a doogee dg 850 hitman, but there are no roms so i would like to create one or port it from an other device.
The problem is the doogee hitman is not very famous so i am searching for Meta-inf folder, system folder and boot.img but there isnt nothing on google. I want to know how can I extract this files from my device. Thanks, sorry for my english is quite bad.